The liquidity it provides is often very low quality. When liquidity in the old days was added, the players involved had to operate under stricter regulations --

The liquidity it provides is often very low quality. When liquidity in the old days was added, the players involved had to operate under stricter regulations -- they had to post a quote that was part of the National Best Bid and Offer a minimum percentage of time. With HFT it's a wild west scenario. There's a lot of uncertainty and risk of failure in many of its steps.